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13#include <linux/clk.h>
14#include <linux/clockchips.h>
15#include <linux/delay.h>
16#include <linux/interrupt.h>
17#include <linux/irq.h>
18#include <linux/irqreturn.h>
19#include <linux/reset.h>
20#include <linux/slab.h>
21#include <linux/of.h>
22#include <linux/of_address.h>
23#include <linux/of_irq.h>
24
25#define TIMER_IRQ_EN_REG 0x00
26#define TIMER_IRQ_EN(val) BIT(val)
27#define TIMER_IRQ_ST_REG 0x04
28#define TIMER_CTL_REG(val) (0x20 * (val) + 0x10)
29#define TIMER_CTL_ENABLE BIT(0)
30#define TIMER_CTL_RELOAD BIT(1)
31#define TIMER_CTL_CLK_PRES(val) (((val) & 0x7) << 4)
32#define TIMER_CTL_ONESHOT BIT(7)
33#define TIMER_INTVAL_LO_REG(val) (0x20 * (val) + 0x14)
34#define TIMER_INTVAL_HI_REG(val) (0x20 * (val) + 0x18)
35#define TIMER_CNTVAL_LO_REG(val) (0x20 * (val) + 0x1c)
36#define TIMER_CNTVAL_HI_REG(val) (0x20 * (val) + 0x20)
37
38#define TIMER_SYNC_TICKS 3
39
40struct sun5i_timer {
41 void __iomem *base;
42 struct clk *clk;
43 struct notifier_block clk_rate_cb;
44 u32 ticks_per_jiffy;
45};
46
47#define to_sun5i_timer(x) \
48 container_of(x, struct sun5i_timer, clk_rate_cb)
49
50struct sun5i_timer_clksrc {
51 struct sun5i_timer timer;
52 struct clocksource clksrc;
53};
54
55#define to_sun5i_timer_clksrc(x) \
56 container_of(x, struct sun5i_timer_clksrc, clksrc)
57
58struct sun5i_timer_clkevt {
59 struct sun5i_timer timer;
60 struct clock_event_device clkevt;
61};
62
63#define to_sun5i_timer_clkevt(x) \
64 container_of(x, struct sun5i_timer_clkevt, clkevt)
65
66
67
68
69
70
71
72static void sun5i_clkevt_sync(struct sun5i_timer_clkevt *ce)
73{
74 u32 old = readl(ce->timer.base + TIMER_CNTVAL_LO_REG(1));
75
76 while ((old - readl(ce->timer.base + TIMER_CNTVAL_LO_REG(1))) < TIMER_SYNC_TICKS)
77 cpu_relax();
78}
79
80static void sun5i_clkevt_time_stop(struct sun5i_timer_clkevt *ce, u8 timer)
81{
82 u32 val = readl(ce->timer.base + TIMER_CTL_REG(timer));
83 writel(val & ~TIMER_CTL_ENABLE, ce->timer.base + TIMER_CTL_REG(timer));
84
85 sun5i_clkevt_sync(ce);
86}
87
88static void sun5i_clkevt_time_setup(struct sun5i_timer_clkevt *ce, u8 timer, u32 delay)
89{
90 writel(delay, ce->timer.base + TIMER_INTVAL_LO_REG(timer));
91}
92
93static void sun5i_clkevt_time_start(struct sun5i_timer_clkevt *ce, u8 timer, bool periodic)
94{
95 u32 val = readl(ce->timer.base + TIMER_CTL_REG(timer));
96
97 if (periodic)
98 val &= ~TIMER_CTL_ONESHOT;
99 else
100 val |= TIMER_CTL_ONESHOT;
101
102 writel(val | TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
103 ce->timer.base + TIMER_CTL_REG(timer));
104}
105
106static int sun5i_clkevt_shutdown(struct clock_event_device *clkevt)
107{
108 struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt);
109
110 sun5i_clkevt_time_stop(ce, 0);
111 return 0;
112}
113
114static int sun5i_clkevt_set_oneshot(struct clock_event_device *clkevt)
115{
116 struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt);
117
118 sun5i_clkevt_time_stop(ce, 0);
119 sun5i_clkevt_time_start(ce, 0, false);
120 return 0;
121}
122
123static int sun5i_clkevt_set_periodic(struct clock_event_device *clkevt)
124{
125 struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt);
126
127 sun5i_clkevt_time_stop(ce, 0);
128 sun5i_clkevt_time_setup(ce, 0, ce->timer.ticks_per_jiffy);
129 sun5i_clkevt_time_start(ce, 0, true);
130 return 0;
131}
132
133static int sun5i_clkevt_next_event(unsigned long evt,
134 struct clock_event_device *clkevt)
135{
136 struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt);
137
138 sun5i_clkevt_time_stop(ce, 0);
139 sun5i_clkevt_time_setup(ce, 0, evt - TIMER_SYNC_TICKS);
140 sun5i_clkevt_time_start(ce, 0, false);
141
142 return 0;
143}
144
145static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id)
146{
147 struct sun5i_timer_clkevt *ce = (struct sun5i_timer_clkevt *)dev_id;
148
149 writel(0x1, ce->timer.base + TIMER_IRQ_ST_REG);
150 ce->clkevt.event_handler(&ce->clkevt);
151
152 return IRQ_HANDLED;
153}
154
155static int sun5i_rate_cb_clksrc(struct notifier_block *nb,
156 unsigned long event, void *data)
157{
158 struct clk_notifier_data *ndata = data;
159 struct sun5i_timer *timer = to_sun5i_timer(nb);
160 struct sun5i_timer_clksrc *cs = container_of(timer, struct sun5i_timer_clksrc, timer);
161
162 switch (event) {
163 case PRE_RATE_CHANGE:
164 clocksource_unregister(&cs->clksrc);
165 break;
166
167 case POST_RATE_CHANGE:
168 clocksource_register_hz(&cs->clksrc, ndata->new_rate);
169 break;
170
171 default:
172 break;
173 }
174
175 return NOTIFY_DONE;
176}
177
178static int __init sun5i_setup_clocksource(struct device_node *node,
179 void __iomem *base,
180 struct clk *clk, int irq)
181{
182 struct sun5i_timer_clksrc *cs;
183 unsigned long rate;
184 int ret;
185
186 cs = kzalloc(sizeof(*cs), GFP_KERNEL);
187 if (!cs)
188 return -ENOMEM;
189
190 ret = clk_prepare_enable(clk);
191 if (ret) {
192 pr_err("Couldn't enable parent clock\n");
193 goto err_free;
194 }
195
196 rate = clk_get_rate(clk);
197
198 cs->timer.base = base;
199 cs->timer.clk = clk;
200 cs->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clksrc;
201 cs->timer.clk_rate_cb.next = NULL;
202
203 ret = clk_notifier_register(clk, &cs->timer.clk_rate_cb);
204 if (ret) {
205 pr_err("Unable to register clock notifier.\n");
206 goto err_disable_clk;
207 }
208
209 writel(~0, base + TIMER_INTVAL_LO_REG(1));
210 writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
211 base + TIMER_CTL_REG(1));
212
213 ret = clocksource_mmio_init(base + TIMER_CNTVAL_LO_REG(1), node->name,
214 rate, 340, 32, clocksource_mmio_readl_down);
215 if (ret) {
216 pr_err("Couldn't register clock source.\n");
217 goto err_remove_notifier;
218 }
219
220 return 0;
221
222err_remove_notifier:
223 clk_notifier_unregister(clk, &cs->timer.clk_rate_cb);
224err_disable_clk:
225 clk_disable_unprepare(clk);
226err_free:
227 kfree(cs);
228 return ret;
229}
230
231static int sun5i_rate_cb_clkevt(struct notifier_block *nb,
232 unsigned long event, void *data)
233{
234 struct clk_notifier_data *ndata = data;
235 struct sun5i_timer *timer = to_sun5i_timer(nb);
236 struct sun5i_timer_clkevt *ce = container_of(timer, struct sun5i_timer_clkevt, timer);
237
238 if (event == POST_RATE_CHANGE) {
239 clockevents_update_freq(&ce->clkevt, ndata->new_rate);
240 ce->timer.ticks_per_jiffy = DIV_ROUND_UP(ndata->new_rate, HZ);
241 }
242
243 return NOTIFY_DONE;
244}
245
246static int __init sun5i_setup_clockevent(struct device_node *node, void __iomem *base,
247 struct clk *clk, int irq)
248{
249 struct sun5i_timer_clkevt *ce;
250 unsigned long rate;
251 int ret;
252 u32 val;
253
254 ce = kzalloc(sizeof(*ce), GFP_KERNEL);
255 if (!ce)
256 return -ENOMEM;
257
258 ret = clk_prepare_enable(clk);
259 if (ret) {
260 pr_err("Couldn't enable parent clock\n");
261 goto err_free;
262 }
263
264 rate = clk_get_rate(clk);
265
266 ce->timer.base = base;
267 ce->timer.ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
268 ce->timer.clk = clk;
269 ce->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clkevt;
270 ce->timer.clk_rate_cb.next = NULL;
271
272 ret = clk_notifier_register(clk, &ce->timer.clk_rate_cb);
273 if (ret) {
274 pr_err("Unable to register clock notifier.\n");
275 goto err_disable_clk;
276 }
277
278 ce->clkevt.name = node->name;
279 ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
280 ce->clkevt.set_next_event = sun5i_clkevt_next_event;
281 ce->clkevt.set_state_shutdown = sun5i_clkevt_shutdown;
282 ce->clkevt.set_state_periodic = sun5i_clkevt_set_periodic;
283 ce->clkevt.set_state_oneshot = sun5i_clkevt_set_oneshot;
284 ce->clkevt.tick_resume = sun5i_clkevt_shutdown;
285 ce->clkevt.rating = 340;
286 ce->clkevt.irq = irq;
287 ce->clkevt.cpumask = cpu_possible_mask;
288
289
290 val = readl(base + TIMER_IRQ_EN_REG);
291 writel(val | TIMER_IRQ_EN(0), base + TIMER_IRQ_EN_REG);
292
293 clockevents_config_and_register(&ce->clkevt, rate,
294 TIMER_SYNC_TICKS, 0xffffffff);
295
296 ret = request_irq(irq, sun5i_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
297 "sun5i_timer0", ce);
298 if (ret) {
299 pr_err("Unable to register interrupt\n");
300 goto err_remove_notifier;
301 }
302
303 return 0;
304
305err_remove_notifier:
306 clk_notifier_unregister(clk, &ce->timer.clk_rate_cb);
307err_disable_clk:
308 clk_disable_unprepare(clk);
309err_free:
310 kfree(ce);
311 return ret;
312}
313
314static void __init sun5i_timer_init(struct device_node *node)
315{
316 struct reset_control *rstc;
317 void __iomem *timer_base;
318 struct clk *clk;
319 int irq;
320
321 timer_base = of_io_request_and_map(node, 0, of_node_full_name(node));
322 if (IS_ERR(timer_base))
323 panic("Can't map registers");
324
325 irq = irq_of_parse_and_map(node, 0);
326 if (irq <= 0)
327 panic("Can't parse IRQ");
328
329 clk = of_clk_get(node, 0);
330 if (IS_ERR(clk))
331 panic("Can't get timer clock");
332
333 rstc = of_reset_control_get(node, NULL);
334 if (!IS_ERR(rstc))
335 reset_control_deassert(rstc);
336
337 sun5i_setup_clocksource(node, timer_base, clk, irq);
338 sun5i_setup_clockevent(node, timer_base, clk, irq);
339}
340CLOCKSOURCE_OF_DECLARE(sun5i_a13, "allwinner,sun5i-a13-hstimer",
341 sun5i_timer_init);
342CLOCKSOURCE_OF_DECLARE(sun7i_a20, "allwinner,sun7i-a20-hstimer",
343 sun5i_timer_init);
344
